Quasimoto

Quasimoto, or producer Madlib's alter ego emcee, hails from Oxnard, California.
One day in the studio, Madlib decided to rap to his own beats. He didn't like the sound of his voice (his friends in Oxnard call him 'Barry White' in reference to his deep voice) so decided to simply change the pitch of the vocals to produce Quasimoto's distinctive high pitched voice. The debut album was conceived and recorded by Madlib during a week long psilocybin mushroom binge. 'Lord Quas' has released two LPs: "The Unseen", and "The Further Adventures of Lord Quas". And several EP's as Astronaut and Broad Factor.

As quoted on Quaz's MySpace page:

Quasimoto is not from outer space. He's from Lost Gates.
Quasimoto does not use helium. He uses a mic.
Quasimoto will not go to your page to listen to your beats.